Pike Musky Or Hybrid?

Colorado initiated their musky stocking program in 1983. In the years following the Division continued stocking the hybrid tiger musky. Today there are over 50 lakes and reservoirs stocked. Since 1983 the Division of Wildlife has stocked over 568,000 musky hybrids.

For a number of years there have been stories about fishermen catching tiger musky’s and/or true muskellunge in waters that have not been stocked by the Colorado Division of Wildlife. Numerous individuals have stopped by the Muskies, Inc. booth at the sports shows and told of catching musky’s themselves from lakes and reservoirs like Spinney, Eleven Mile, Taylor Park, Williams Fork, Tarryall, and even in the Yampa River. Up to now their stories have been ignored.
Recently, I was able to obtain some “no doubt about it” photos of tiger musky’s caught from Eleven Mile Reservoir. Not wanting to be talked out of the truth, I solicited two very well respected and renowned experts on muskellunge identification. One was Bob Strand, Regional Fisheries Manager, Minnesota Department of Natural Resources. The other individual was Dr. Ed Crossman, Curator Emeritus (Ichthyology) Royal Ontario Museum. Both gentlemen have written extensively and authored numerous technical papers. In Dr. Crossman’s case he co-authored the technical paper in Managing Muskies entitled “Identification of Muskellunge, Northern Pike and their Hybrids.” Both of these musky experts confirmed the photos I sent them as definitely hybrid tiger muskies. Eddie Kochman, Colorado State Aquatic Wildlife Manager, has cautiously agreed.

Recently I had an opportunity to discuss these photos with Dr. John Casselman of the Ontario Ministry of Natural Resources. I sent him my collection of photos. His conclusion of these specific photos was that they were northern pike. He said, “I consider the above fish to be a northern pike with variant colour pattern. Whether there are other esocid attributes is difficult to ascertain from the photograph. But relative head length suggests to me that it is probably a northern pike (moderate certainty)”.

Regarding a photo of two smaller fish on the ice, Dr. Casselman says, “both fish are northern pike. One of the fish has vertical barring that is often prominent in young northern pike of its size. The colour pattern is not indicative of the young of hybrids or muskellunge”.

Where possible, Dr. Casselman tries to measure the head length and relate it to total length. He states that, “ a hybrid shows what is referred to as ‘hybrid vigor’ in bone growth”.

They actually have larger bones. As a result they have disproportionately longer heads relative to body length”. He goes on to say that, “hybrids I have examined have had head lengths that exceed 27% of total body length”. This is the primary basis for his determination that the photos are of pike.

So here you have two different scientific opinions from the professional community. The truth is that there is a need to seriously fish these lakes and reservoirs and capture some true muskellunge or hybrids for positive identification.

There have been a number of theories suggested, if in fact, these fish are pure muskellunge or hybrids.

First there is the “bucket biology” theory. There exists photos of fish from various year classes and a number of affidavits and photos to make any serious illegal stocking to be doubtful, at best. Too many fish, too many locations (lakes), too many different age classes for any illegal stocking. After all, hybrid tiger muskie are sterile and have been scientifically proven so, most recently by Dr. Jim Satterfield, PhD. (Colorado Division of Wildlife, Central Region Biologist)

Next, due to all the different age classes of hybrids, most theorists would surmise that there exists natural muskellunge within the reservoirs where the hybrids are showing up. Some “experts” question the different color variations of the suspect fish. Dr. Crossman suggests that there could be hybrid crosses of male pike-female muskellunge, as well as the other way, i.e. male muskellunge-female pike.

Joe Bucher and Otis Smith authored an article “Similarities And Differences Between Muskies and Pike”. In this article they explained that the pike have white or light colored oblong spots against a dark (usually green) background. There also exists a “silver” pike which appears to be absent of the spots and has dark to light grayish-blue sides. I am unaware of any literature or any person(s) who have reported catching pike with any other coloration than the oblong spots in a horizontal pattern, not a vertical bar pattern. Also you may notice on these fish that the fins are quite reddish, typical of a hybrid.

Anyone fishing Colorado waters should be aware that the Statewide size regulation of tiger muskie is 30” except for Quincy Reservoir which has a 40” regulation. With regard to the true muskellunge, they are not recognized as a species in Colorado, thus no regulation. You can catch and keep any true muskellunge.

Now comes the $64.00 question. Where did these true muskellunge come from, if in fact, they are producing these hybrid tiger musky’s? Some theories are that the true muskellunge were stocked legally and possibly accidentally, by the Division of Wildlife. The Division of Wildlife began stocking northern pike around 1956. Back in those days and until recently, it could have been entirely possible that the northern pike fry traded with mid-western states like Wisconsin and others may have contained a percentage of true muskellunge mixed in with the northern pike fry. There are, of course, many other ideas. The search for the truth is very important to Colorado and other western states.Important because the U.S. Fish & Wildlife Service as well as various environmental groups are making a concerted effort to prevent stocking of non-native species in anywaters west of the Continental Divide.

It took exactly five years of political and, sometimes not so political, wrangling with the “Service” for Colorado to obtain permission to stock the hybrid tiger musky at Harvey Gap Reservoir on the western slope. This issue about stocking non-native species goes beyond the hybrid tiger musky. It includes such fish as wipers, channel catfish, and others. The environmentalists have begun a movement to prevent all fish species other than the salmonids (trout). This is all due to the protection of the “threatened and endangered species” ie, the Colorado River squawfish, humpback chub, razorback sucker, bonytailed chub.

There are six western states with musky’s and/or hybrids in their waters and musky stocking programs within their Natural Resource Departments. These states are all affected by this 1960’s Endangered Species Act (ESA) which was revised in 1973. It is interesting to note that in the State of Washington there was reported to be a bounty on “squawfish” of $2.00 each. In fact their Department of Natural Resources has stocked the tiger hybrid musky to control the squawfish populations.

I have regressed somewhat in order to make the point of identifying the “suspect” fish of Colorado. If, in fact, these barred fish are hybrids or a non-native fish of some sort that presently and quite possibly for some time have resided on Colorado’s western slope we have a precedent setting occurrence. If this is the case, there may be an even bigger challenge for those of us who espouse expanding the musky range.